Pressure Ohmic Thawing: a Feasible Approach for the Rapid Thawing of Frozen Meat and Its Effects on Quality Attributes

摘要

Rapid thawing has its significance to minimize the changes in quality attributes and microbial growth of frozen foods. This study investigated the potential of pressure ohmic thawing (POT) which utilize the synergy of high-pressure thawing and ohmic thawing. POT refers to the thawing of frozen foods using ohmic thawing (40 V/cm) under elevated pressures (200 MPa). Custom developed POT system was composed of flexible ohmic cell, pressure chamber, and electric field supplying system. Frozen beef samples in POT cells that were thawed with POT (40 V/cm, 200 MPa) were compared to control samples thawed using conventional, ohmic, and pressure-assisted thawing (PAT). POT had the shortest thawing time (0.8 min) followed by ohmic (5.5 min), PAT (11.5 min), and conventional thawing (43.3 min). POT and PAT applications decreased melting points of frozen samples from -1.6 A degrees C at 0.1 MPa to -27 A degrees C at 200 MPa. In POT, the in situ electrical conductivity increased (0.2-1.0 S/m), which combined with decreased melting points possibly enabled quicker thawing. POT minimized changes in shear force tests and peak forces close to that of raw sample as compared to controls. Our study demonstrates the benefits of POT applications for rapid thawing without affecting meat quality.